Topological Pair-Density-Wave Superconducting States
Abstract
We show that the pair-density-wave (PDW) superconducting state emergent in extended Heisenberg-Hubbard models in two-leg ladders is topological in the presence of an Ising spin symmetry and supports a Majorana zero mode (MZM) at an open boundary and at a junction with a uniform -wave one-dimensional superconductor. Similarly to a conventional finite-momentum paired state, the order parameter of the PDW state is a charge- field with finite momentum. However, the order parameter here is a {\it quartic} electron operator and conventional mean-field theory cannot be applied to study this state. We use bosonization to show that the 1D PDW state has a MZM at a boundary. This superconducting state is an exotic topological phase supporting Majorana fermions with finite-momentum pairing fields and charge- superconductivity.
Cite
@article{arxiv.1407.6358,
title = {Topological Pair-Density-Wave Superconducting States},
author = {Gil Young Cho and Rodrigo Soto-Garrido and Eduardo Fradkin},
journal= {arXiv preprint arXiv:1407.6358},
year = {2014}
}
Comments
5+epsilon pages, 45 references, 5 pages of supplemental material; v3: improved presentation, to appear in Phys. Rev. Lett